uikit

问题 I am contemplating a simple app that has four characters that you can drag around on the screen. While dragging they "wiggle" — that's the animation. And they snap to a position if they get close enough to it... like in a puzzle. Without the animation, this is all simple in UIKit. My first thought is to render each character in its own SKView inside a plain old UIView . I could attach UIGestureRecognizers to each SKView to track tapping and dragging. But I think this implies individual

问题 I have this scenario: My action sheets have a variant text size, like in this question, but trying to access this API from xamarin iOS, I cant find the property: UILabel.appearance(whenContainedInInstancesOf: [UIAlertController.self]).numberOfLines = 2 Reading this question, anwsered by @SushiHangover, there are many hidden API's by Xamarin, and with the code, I think I can achieve the desired behavior. So, in Xamarin.iOS, how can I force my action sheet's options to have two or more lines of

问题 I've written some code that moves some objects around on the screen in sequence. As each object finishes moving, the next starts. The code is structured similarly to this: Model: moveObject { // Code to move the object ... [delegate moved:self]; } Delegate: moved:(MyClass *)o { UIView* v = [self viewForObject:o]; [UIView animateWithDuration:1.0 animations:^{ [v setCenter: [model center]]; } completion:^(BOOL finished){ // Move object [model moveObject]; }]; } Although the code seems to run

问题 I have this code to draw rounded rectangles: void ContextAddRoundedRect(CGContextRef ctx, CGRect rect, CGFloat radius) { CGFloat minX = CGRectGetMinX(rect); CGFloat maxX = CGRectGetMaxX(rect); CGFloat minY = CGRectGetMinY(rect); CGFloat maxY = CGRectGetMaxY(rect); CGContextMoveToPoint(ctx, minX + radius, minY); CGContextAddArcToPoint(ctx, maxX, minY, maxX, minY + radius, radius); CGContextAddArcToPoint(ctx, maxX, maxY, maxX - radius, maxY, radius); CGContextAddArcToPoint(ctx, minX, maxY, minX

问题 Is it anyway possible to observe if a UIAlertView is being displayed and call a function when it is. The UIAlertView is not being created and displayed in the same class which I want a function to be called in. Its hard to explain but to put it simply I need to somehow monitor or observe if the view becomes like out of first responder or something because I dont think it is possible to monitor if a UIAlertView is being displayed :/ 回答1: Sounds like a job for notifications. Say that class A

问题 My UITableView data source gets updated in background thread based on user action. And I am reDisplaying cells in foreground. Problem is if number of rows in new data is less than the number of rows in previous data, I can still see old rows listed after the new rows. After 15-20 seconds these old rows are automatically deleted (sometimes it is faster). Or if I go to different screen and comeback to my tableview (with the datasource unchanged), the old rows are no more there. My guess is

问题 I'm working on an iOS project where I want to dynamically add more cell to the bottom of the tableview once the user reaches the bottom. I currently have this working by calling a method that fetches more data that is added to the array that I'm using to hold my cells. When I'm done adding the objects to the array I call [tableView reloadData]. This works, but it doesn't visually load the cell until the tableview stops scrolling. I also tried using [tableView insertRowsAtIndexPaths: inSection

问题 This question was migrated from Software Engineering Stack Exchange because it can be answered on Stack Overflow. Migrated 5 years ago . I have an app that just needs one screen to autorotate, the first and last screens should be portrait. I can get the last screen to stop rotating using: - (NSUInteger)supportedInterfaceOrientations { return UIInterfaceOrientationMaskPortrait; } But this does not work on the first screen, I am using a storyboard with a UINavigationController (I'm thinking

问题 I have a UIView inside my xib in IB and inside that is a UIScrollview that is a small 80x80 square and dynamically loaded with 8 or so 80 x 80 thumbnail images. The UIScrollview is not clipping the images so that they extend out either side so you can swipe left and right to scroll a chosen image into the the centre, paging is on so they snap ti each image. I have researched and found this is the best and possibly only way to do this. The UIScrollview sits in a 'container' UIView for one

问题 I have a UITextView to display the title and content of an article. Here is my code: static func setTextViewRichText(textView: UITextView, html: String, title: String) { do { let titleText = NSAttributedString(string: title + "\n", attributes: [NSFontAttributeName: UIFont(name: "Helvetica", size: 20)!]) let contentText = try NSAttributedString(data: html.dataUsingEncoding(NSUTF8StringEncoding)!, options: [NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType,